Acyl substituted reactive methylene color couplers



Patented Feb. 17, 1948 ACYL SUBSTITUTED REACTIV'E METHYL- ENE COLOR COUPLERS Arnold Weissberger, Charles J. Kibler, vand Henry D. Porter, Rochester, N. Y., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Drawing. Application November 25, 1944, Serial No. 565,190

6 Claims.

'1 This invention relates to color photography and particularly to color-forming or coupling One method of rendering the coupler non-diffusing in the emulsion layer is to incorporate in the non-coupling portion of the molecule a long chain or other complex group which hinders diffusion of the coupler. This difiusion preventing group remains in the final dye image and renders the resulting dye needlessly complex, since it generally does not contribute to the light absorption properties of the dye.

The following examples illustrate compounds which may be used according to our invention:

compounds. A 1. onlo=on-cooclm The formation of colored photographic images by using a primary aromatic amino developing Coca agent which couples with color-forming com- E y -a ylw pounds on development has been the subject of numerous prior patents. Most of these patents GO'CH have been directed to coupler compounds which -produce on development dyes which meet the 10 Ethyl-O-benzoyl-acetoacetate requirements of subtractive color photography,

that is, dyes which are colored yellow, magenta c H or blue-green and many have been directed to methods for rendering the couplers non-difiusing in the silver halide emulsion. 000.11.

l-benzoyl-3-benzoylamino-5-benzoyloxypyrazole O C 0 CIHB l-(2'-benzothiazo1yl)-3-benzoylamino-S-benzoyloxypyrazole We have found that if an acyl group is 5 N=CNHCOCH attached to the carbon atom of the reactive 06H methylene group of couplers containing such group, or through an oxygen atom to a carbon C: H atom adjacent to the reactive methenyl group of ococHl the enolic form of such couplers, compounds 1 pheny1 3 mty1amiwmcetoxypymmm result which have desirable properties for purposes of color photography. The coupling reac- N=CNHC@H tion is a vigorous one which splits 03 the acyl 0.13m group and presumably forms the same dye as C: H would be produced from the coupler not containing the acyl group. The presence of the acyl group. however, introduces desirable properties l-phenyl-il anilIno-S-benzoyloxypyrazole into the coupler. as will be explained more fully hereinafter. 1. COHICOCHCONHCJHJ The couplers which we propose to use have 0 0cm one of the following general formulas: g h t t flld 1 xc=cn-Y 1 8. CIHICOCHCONHCOHI m or 0mm X--CO(|JHY mDlbenroyl-wetanilide a olmcocncooolm where X=alkyl or aryl. Y=--COOC2H5 or OCH CONH-aryl. or X and Y together represent the atoms necessary to complete a pyrazolone ring. so "bemylmwmww l0. CHICOCHCOOClHI Ethyl dlacetyl-ucetate ll. C;H CH COCHCO0C|H O CH:

Ethyl -(phenylacetyl) acetoacetate The acyl radical in the general Formulas 1 and 2 above may be a radical such as acetyl, propionyl, butyryl, or benzoyl, or a higher fatty acid acyl radical such as lauroyl. If the acyl group is a radical of appropriate size, the coupler may be incorporated in an emulsion layer of a multilayer material and is non-difiusing in the layer. When coupling occurs, the acyl group is split ofi and the resulting dye is a simple molecule containing no long chain or other complex group which is unnecessary in the final dye. Obviously, the lower fatty acid acyl groups may be used in couplers which are to be incorporated in the developing solution. In certain cases, however, couplers containing such acyl groups might be non-diffusing and suitable for incorporation in an emulsion of a multi-layer coating by reason of other groups in the molecule.

The alkyl and aryl groups in the general Formulas 1 and 2 above may be substitued or unsubstituted. A benzyl group is considered a substituted alkyl radical and it is within the scope of our general formula and claims where we refer to an alkyl radical.

The following example illustrates the use of one of our couplers in the developing solution:

A. 2-amino-5-diethyl-aminotoluene HCl grams 2 Sodium sulfite do 5 Sodium carbonate do 30 Water to -liter 1 B. Ethyl-O-acetylacetoacetate grams 2 Sodium hydroxide solution) cc 10 For use B is added to A.

The aromatic amino developing agents used with the coupler compounds of our invention include the mono-, di-, and tri-amino aryl compounds and their derivatives formed by substitution'in the amino group as well as in the ring, such as alkyl, phenylene diamines and alkyl toluene diamines. These compounds are usually employed in the salt form, such as the hydrochloride or the sulfate which is more stable than the amines themselves. Suitable compounds are diethyl p phenylenediamine hydrochloride, monomethyl-p-phenylene diamine hydrochloride, dimethyl-p-phenylene diamine sulfate, and 2- amino-5-diethylaminotoluene hydrochloride. The p-aminophenols and their substitution products may also be used where the amino group is unsubstituted. All of these developing agents have an unsubstituted amino group to which the oxi dation products of the developer couple with the color-forming compounds to form dye images.

In addition to the advantage of having a diffusion-preventing group in a portion of the molecule which is split on during formation of the dye image, our couplers have the advantage that the activity of the methylene group with compounds other than the oxidized developer is greatly reduced. The couplers cannot participate in undesirable side reactions which tend to produce stain because the activity of the reactive methylene group to many of these reactions is reduced by the presence of the acyl radical. The

color-forming reaction,.. however, is more powerful than many of these side reactions and immediately splits oil the acyl group and forms a coupled dye image.

Our development method may be employed for the production of colored photographic images in layers of gelatin or other carrier such as collodion, organic esters of cellulose or synthetic resins. The carrier may be supported by a transparent medium, such as glass, cellulose ester, or a non-transparent reflecting medium, such as paper or an opaque cellulose ester. The emulsion may be coated as a single layer or as multiple layers on the support or in the case of a transparent support as superposed layers on both sides of the support. The superposed layers may be difierentially sensitized and the dyes formed therein by coupling may be bleached by an oxidizing agent, such as chromic acid to colorless soluble compounds. The destruction of the dye in this way does not destroy the silver image and the silver may be resensitized to develop a color a number of times, thus permitting the formation of neutral colored images in superposed layers as described for example in Mannes and Godowsky U. S. Patent 2,113,329. Colored images may also be formed in the manner described in Mannes and Godowsky and Wilder U. S. Patent 2,252,718.

The examples and compounds set forth in the present specification are illustrative only and it will be understood that our invention is limited only by the scope of the appended claims.

We claim:

1. A color-forming photographic developer comprising a primary aromatic amino developing agent and a coupler compound having a formula selected from the group consisting of where R is a carboxylic acid acyl group, and X and Y are selected from the class consisting of groups in which X is selected from the class consisting of alkyl and aryl, Y is selected from the class consisting of COOC2H5 and -CONH- aryl, and X and Y together represent the atoms necessary to complete a pyrazolone ring.

2. A color-forming photographic developer comprising a primary aromatic amino developing agent and a coupler compound having the formula and where R is a carboxylic acid acyl group, and X and Y are selected from the class consisting of groups in which X is selected from the class consisting of alkyl and aryl, Y is selected from the class consisting of -CO0C2H5 and --CONH- aryl, and X and Y together represent the atoms necessary to complete a pyrazolone ring.

4. The method of producing a colored photographic image in a gelatino-silver halide emul- 1 and sion layer which comprises exposing the layer and developing it with a primary aromatic amino developing agent in the presence of a. coupler compound having the formula:

CHaC=CHC O OCzHg C OCH:

6. A photographic emulsion for forming colored images comprising a water-permeable, colloidal carrier containing a sensitive silver halide and a coupler compound having a formula selected from the group consisting of and X-C=CH-Y where R is a carboxylic acid acyl group, and X and Y are selected from the class consisting of groups in which X is selected from the class consisting of alkyl and aryl, Y is selected from the class consisting of COOC2H5 and -CONH- aryl, and X and Y together represent the atoms necessary to complete a pyrazolone ring.

ARNOLD WEISSBERGER. CHARLES J. KIBLER. HENRY D. PORTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,120,741 Graenacher et al. June 14, 1938 2,213,986 Kendall et al Sept. 10, 1940 2,294,909 Jennings Sept. 8, 1942 2,340,763 McQueen Feb. 1, 1944 

